JK-Q8

I was driving in the desert a week ago and i got to a part where there was very soft sand, and i was in 4hi , and i was in 2nd gear and the jeep started to bog down so i hit it in first gear but the rpms are always at 3500 and its a long distance. Is it ok to drive with so high rpms and slow speed?

muddpuppy01

yes just watch the temp gauge or if you want you could shift to 4lo and run a what ever gear to keep the rpms down but you wont be going very fast

jeeperjkj

Not sure what your gear ratio is, but here goes...

2nd gear in high with 3.73's @ 20 mph (I'd assume you were going about that speed) would yield 2044 rpms

1st gear in high with 3.73's @ 20 mph would yield 3494 rpms (that's why I assumed you were going about 20 mph)

3rd gear in low with 3.73's @ 20 mph would yield 3665 rpms (about the same as 1st gear in high)

4th gear in low with 3.73's @ 20 mph would yield 2663 rpms. That's a little better.

That's why the gear calculators are so good. You can learn where your optimal ratios are at. Sometimes it might be better to be in 4low in a higher gear -vs- being in 4high in a lower gear.

Did that make any sense?

flyer415

Well, I have to admit that I never thought about it that way but d**n if that doesn't make sense. Now I'll just map the similar gears in my head so I can figure out realtime which way to go i.e. 4hi and low gear or 4lo and a high gear.

JK-Q8

I tried 4lo out and i feel its a bit too much for soft soft sand were i need speed. But i didnt try it that day maybe it would be better but also there was alot of hard land so i didnt want to be switching abck and forth from 4hi and 4lo. But doesnt the engine and tranny be under pressure when there are high rps and low speed?

muddpuppy01

no the engine would be under more stress with higher gear lower speed having to chug it way instead of being in a good power spot in the rpm department

the tranny wont notice a difference unless you you are on and off the gas very quickly all the time

unless it a auto then you should kept a eye on the temp of the trans as it can over heat but that problem does not seem to be just to driving in sand as some have has problems in the past

JK-Q8

Okay thanx and what if the rpms are even higher like 4500 is that okay?

jeeperjkj

I wouldn't keep them that high for long.

muddpuppy01

X2 you dont want to redline it but you can get up there 3500 is not bad but I would not do anything over 4000 for anything over 30 seconds if I can

JK-Q8

and wat could happen if it does? wats gona get a beating